The invention relates generally to railcars, and more particularly, to a center beam car.
Center beam cars have proven to be useful in transportation of various materials, including bulk materials such as lumber products which are of high volume and low density. However, there remains room for improvement in certain areas.
First, the usable volume capacity of the center beam car is often reached before the car""s weight capacity is reached. This results in inefficiency, in that the weight carrying capacity of the car is not fully utilized. One of the objects of the invention is to provide a center beam car having capacity to carry loads of increased volume.
Another area for improvement relates to efficiency in loading and unloading the cars. While center beam cars can be loaded and unloaded efficiently with forklifts, loading and unloading by overhead crane is difficult due to the fact that the top chord typically overhangs the load. It is a general object of the invention to provide a center beam car which can be more easily loaded by overhead crane.
A further area for improvement concerns securing loads in place. After a car has been loaded, to secure the load in place, workers have generally been required to climb onto the load to secure cables to the center beam. Winches have been provided on each side of the car, fixed to the side sills at predetermined intervals. Cables are pulled from the winches to the center beam to secure the load. Later, when the car is to be unloaded, workers must again climb onto the car and release the cable ends from the center beams. The need for workers to climb onto the car after loading and prior to unloading adds time and expense to the loading and unloading operations. Application of the cables is further complicated by the fact that it has generally been necessary to employ corner protectors at the upper corners of the lading to protect the lading from damage by the cables. Application and removal of corner protection adds further time and expense to the loading and unloading operations.
The invention provides a center beam railcar that addresses the above concerns without unduly increasing the weight or expense of manufacturing the car. The railcar of the inventor preferably provides increased volume capacity and can be loaded and unloaded by overhead crane. The car also preferably provides an improved system for securing loads.
Preferably, the center beam car of the invention has sufficient volume capacity to enable the full weight capacity of the car to be utilized with certain loads. Thus, the car can xe2x80x9cgross outxe2x80x9d and xe2x80x9ccube outxe2x80x9d at the same time with, e.g., kiln-dried lumber products.
In contrast with the top chords that have been used in center beam railcars in the past, wherein the top chord is significantly wider than the intermediate portion of the center beam below the top chord, the preferred center beam railcar has a narrow top chord that does not interfere with loading by overhead crane, but still contributes significantly to the strength and load carrying capacity of the railcar. The top chord is preferably of a generally rectangular, tubular configuration, and has a width substantially equal to or slightly less than the width of the intermediate portion of the center beam therebelow. This permits the load to be stacked alongside the top chord, increasing the volume of lading that can be accommodated as compared with earlier center beam cars in which the lading generally could be stacked only as high as the bottom of the top chord. The top chord preferably is at a height slightly above the upper ends of the bulkheads.
To further increase the volume of lading that can be carried, the railcar preferably has a depressed central portion. In combination with the narrow top chord, this preferably provides a clear loading height of at least about 14 feet above the depressed central portion. The depressed central portion is located between a pair of higher end portions, each preferably having a length about equal to the length of products to be carried thereon, or a multiple thereof. In one particular embodiment, the length is about 16 feet. The depth of the depression is similarly selected to accommodate products to be carried thereon in a manner that facilitates flexibility in loading products of various sizes. In one embodiment, the depth is 16 in., to enable the depression to accommodate bundles of engineered wood products having a height of 15xc2xd in., with the tops of the bundles being at about the same level as the adjacent end portions of the deck.
To increase versatility in securing the lading on the railcar, the lading is preferably secured by straps, each having a first end secured on a first side of the railcar, and a second end secured on the opposite side of the railcar, with the strap extending over the top chord for materials that are stacked up to the top chord, and with the strap extending under the top chord for materials which are not stacked as high.
In the preferred embodiment of the invention, the straps are secured at or near the side sills on both sides of the car, thus avoiding the need for workers to climb onto the deck or onto the load to secure the load. This also eliminates the need to provide winches on both sides of the car. Winches may be provided only on one side, with a simple mechanism for securing a strap end provided on the other side. Furthermore, to increase versatility, the winches and mechanisms that are used to retain the ends of the straps preferably are longitudinally adjustable in tracks on the side of the railcar.
The straps may be passed over the lading from one side of the car to the other by coiling a portion of the strap containing a free end, while leaving the other end attached to a winch, and manually tossing the coiled strap portion from one side of the car to the other. This may be efficiently accomplished by a worker standing with his or her back to the railcar, tossing the coiled strap over his or her shoulder.
At its ends, the center beam may include one or more elongated supports that connect the bulkheads to one or more posts. The supports need not be connected to the center sill or to the top chord.